Renewable Portfolio Standards
Environmental and Energy Study Institute (EESI) briefing about renewable portfolio standards. in their words:
A Renewable Portfolio Standard (RPS) is a market-based mechanism that requires utilities to gradually increase the portion of electricity produced from renewable resources such as wind, biomass, geothermal, solar energy, incremental hydropower and marine energy.
One panelist, Chris Namovicz is listed as an Operations Research Analyst with the Energy Information Administration (EIA). Briefing link above has link to his slides. That and EIA website could be good follow-ups.
Fundamentally, an RPS involves a constraint, e.g. 15% of a utility’s generated energy must be renewable. Penalties, bonuses, and credits can all come into play.